Table 2.
Operating characteristics of the HEP score and 4Ts score by patient population
| Model | AUC (95% CI) | P* | Cutoff | Sensitivity, % (95% CI)† | Specificity, % (95% CI)† | PPV, % (95% CI)† | NPV, % (95% CI)† |
|---|---|---|---|---|---|---|---|
|
Total population, n = 292: HIT prevalence, 14.7% |
|||||||
| HEP score | 0.81 (0.74-0.87) | .12 | 3 | 95.3 (84.2-99.4) | 35.7 (29.8-42.0) | 20.4 (15.1-26.6) | 97.8 (92.3-99.7) |
| 4Ts score | 0.76 (0.67-0.84) | 4 | 97.7 (86.2-99.8) | 32.9 (27.2-39.1) | 20.1 (15.0-26.3) | 98.8 (92.5-99.9) | |
|
Medical patients, n = 129: HIT prevalence, 12% |
|||||||
| HEP score | 0.81 (0.73-0.90) | .42 | 3 | 100 (79.4-100) | 28.3 (20.2-37.6) | 16.5 (9.73-25.4) | 100 (89.1-100) |
| 4Ts score | 0.78 (0.67-0.88) | 4 | 100 (79.4-100) | 27.4 (19.5-36.6) | 16.3 (9.6-25.2) | 100 (88.0-100) | |
|
Surgical patients, n = 163: HIT prevalence, 17% |
|||||||
| HEP score | 0.82 (0.72-0.91) | .13 | 3 | 92.6 (75.7-99.1) | 41.9 (33.5-50.7) | 24 (16.2-33.4) | 96.6 (88.3-99.6) |
| 4Ts score | 0.76 (0.67-0.84) | 4 | 96.3 (81.0-99.9) | 37.5 (29.4-46.2) | 23.4 (15.9-32.4) | 98.1 (89.7-100) | |
|
Cardiothoracic surgery patients, n = 125: HIT prevalence, 13% |
|||||||
| HEP score | 0.74 (0.61-0.87) | .43 | 3 | 87.3 (61.7-98.4) | 44 (34.5-53.9) | 18.7 (10.6-29.3) | 96.0 (86.3-99.5) |
| 4Ts score | 0.69 (0.57-0.80) | 4 | 93.8 (69.8-99.8) | 39.4 (30.2-49.3) | 18.5 (10.8-28.7) | 97.3 (88.0-99.0) | |
|
ICU patients, n = 170: HIT prevalence, 13% |
|||||||
| HEP score | 0.86 (0.80-0.93) | .03 | 3 | 100 (84.6-100) | 40.5 (32.6-48.9) | 20 (13.0-28.7) | 100 (94.0-100) |
| 4Ts score | 0.79 (0.71-0.88) | 4 | 100 (81.5-100) | 31.1 (23.8-39.2) | 17.7 (11.7-25.8) | 100 (92.3-100) |
*
P value represents comparison of the AUC using the method of DeLong et al.17
†
Exact binomial CIs displayed for sensitivity, specificity, PPV, and NPV.